The following are from my 25-year old notebook:
"Tridacna": 180 PPFD (PAR)
"Tridacna": 85
T. maxima: 160
T. maxima: 250
T. gigas: 120
T. gigas: 286 - Smithsonian tank. Clam was 10 years old.
T. gigas: 130
Hippopus hippopus: 400
These measurements were made in tanks from Baltimore to Seattle. Instrument was a Li-Cor quantum meter with submersible probe, calibrated for underwater readings. The question that arose in another thread was now to 'balance' light intensities to satisfy both Tridacna and Acropora. PPFD of 300 should be that balance.
"Tridacna": 180 PPFD (PAR)
"Tridacna": 85
T. maxima: 160
T. maxima: 250
T. gigas: 120
T. gigas: 286 - Smithsonian tank. Clam was 10 years old.
T. gigas: 130
Hippopus hippopus: 400
These measurements were made in tanks from Baltimore to Seattle. Instrument was a Li-Cor quantum meter with submersible probe, calibrated for underwater readings. The question that arose in another thread was now to 'balance' light intensities to satisfy both Tridacna and Acropora. PPFD of 300 should be that balance.